The present invention relates to inking arrangements for printing presses.
Usual printing presses have an ink fountain roller disposed close to an ink fountain member forming an ink fountain, from which ink is applied to the outer peripheral surface of the fountain roller, then transferred by a vibrating roller to an ink distributing roller and further supplied to the printing surface via a plurality of other ink distributing rollers.
The ink fountain member, which is usually in the form of a plate, and the fountain roller define an ink channel, through which the ink in the fountain is applied to the otuer peripheral surface of the fountain roller.
With the printing press described, the kind of ink to be used is changed depending on the print to be made. In such a case, completion of the preceding printing operation is followed by a procedure for replacing the ink within the fountain by the one to be used for the subsequent printing operation. This replacement procedure includes collection of the old ink from inside the fountain and cleaning of the fountain member and the rollers.
With the conventional printing press, the vibrating roller and the ink distributing rollers are automatically cleaned by so-called inker cleaning, whereas the fountain roller and the fountain member are difficult to clean automatically and are therefore cleaned manually in the following manner. After the preceding printing operation has been completed, the old ink remaining in the fountain is removed by manual work with the fountain roller at rest, and the portions of the fountain roller and the fountain member in contact with the ink are manually cleaned. Accordingly, the old ink is cumbersome to collect, and the fountain member and the fountain roller need to be cleaned by hand, necessitating similarly cumbersome work. Since it is only after these components have been cleaned that new ink can be placed into the fountain, the replacement is a time-consuming procedure and requires a long period of time before starting the next printing operation.
There are also cases wherein the size (width) of the ink channel is altered depending on the print to be produced by the printing machine. In such a case, the size of the ink channel is adjusted conventionally by varying the position or angle of the fountain member, but the adjustment is also cumbersome.
Furthermore it is desired with the printing press to adjust the width of the ink fountain in accordance with the width of the printing surface, whereas this is generally difficult.